Information Notice 1979-24, Overpressurization of Containment of a PWR Plant After a Main Steam Line Break

Overpressurization of Containment of a PWR Plant After a Main Steam Line Break

ML031180172
Person / Time
Site:	05000000
Issue date:	10/01/1979
From:	NRC/IE
To:
References
IN-79-024, NUDOCS 7908220123
Download: ML031180172 (3)

SSINS: 6870

Accession No:

7908220123 UNITED STATES

NUCLEAR REGULATORY COMMISSION

OFFICE OF INSPECTION AND ENFORCEMENT

WASHINGTON, D. C. 20555 October 1, 1979 IE Information Notice No. 79-24 LINE BREAK

OVERPRESSURIZATION OF CONTAINMENT OF A PWR PLANT AFTER A MAIN STEAM

7, 1979 that

Virginia Electric and Power Co. submitted a report dated September pressurization

identified a deficiency in the original analyses of containment

Units 3 and 4.

as a result of a steam line break for North Anna Power Station, of containment

Stone and Webster Engineering Corporation performed a reanalyses

determined that, if the auxiliary

pressure following a main steam line break and to the steam

feedwater system continued to supply feedwater at runout conditions

line break, containment design pressure

generator that had experienced the steam of the

would be exceeded in approximately 10 minutes. The long term blowdown

by the auxiliary feedwater system had

water supplied under runout conditions is now under

not been considered in the earlier analyses. The corrective action

review by the owner, architect engineer, and NSSS supplier.

This Information Notice is provided as an early notification of aItpossibly is expected

significant matter that is still under review by the NRC staff. to their

that recipients will review the information for possible applicability

response is requested at this time. If NRC

facilities. No specific action or or required.

evaluations so indicate, further licensee actions may be requested

you have any

No written response to this Information Notice is required. If the appropriate

questions regarding this matter please contact the Director of

NRC Regional Office.

IE Information Notice No. 79-24 .October 1, 1979 LISTING OF IE INFORMATION NOTICES

ISSUED IN LAST SIX MONTHS

Information Subject Date Issued To

Notice No. Issued

79-10 Nonconforming Pipe 4/16/79 All power reactor

Support Struts facilities with a

CP

Lower Reactor Vessel Head 5/7/79 All holders of Reactor

79-11 Insulation Support Problem OLs and CPs

79-12 Attempted Damage to New 5/11/79 All Fuel Facilities

Fuel Assemblies Research Reactors, and Power Reactors

with an OL or CP

79-13 Indication of Low Water 5/29/79 All Holders of Reactor

Level in the Oyster Creek OLs and CPs

Reactor

79-14 NRC Position of Electrical 6/11/79 All Power Reactor

Cable Support Systems Facilities with a

CP

79-15 Deficient Procedures 6/7/79 All Holders of Reactor

OLs and CPs

79-16 Nuclear Incident at Three 6/22/79 All Research Reactors

Mile Island and Test Reactors

with OLs

79-17 Source Holder Assembly Damage 6/20/79 All Holders of Reactor

Damage From Misfit Between OLs and CPs

Assembly and Reactor Upper

Grid Plate

Skylab Reentry 7/5/79 All Holders of Reactor

79-18 OLs

79-19 Pipe Cracks In Stagnant 7/17/79 All Holders of Reactor

Borated Water Systems At OLs and CPs

PWR Plants

IE Information Notice No. 79-24 Enclosure

October 1, 1979 LISTING OF IE INFORMATION NOTICES

ISSUED IN 1979 Information Subject Date Issued To

Notice No. Issued

79-20 NRC Enforcement Policy 8/10/7'9 All Holders of Reactor

NRC Licensed Individuals OLs and CPs and Production

Licensees with Licensed

Operators

79-21 Transportation and Commercial 9/7/79 All power and research

Burial of Radioactive Material reactors with OL's

79-22 Qualification of Control 9/14/7!9 All power reactor

Systems facilities with

operating licenses

and construction permits.

79-23 Emergency Diesel Generator 9/26/7!9 All Power facilities

Lube Oil Coolers holding OLs and CPs